Enforce or disallow newlines between operands of ternary expressions (multiline-ternary)

要求或禁止在三元操作数中间换行 (multiline-ternary)

JavaScript allows operands of ternary expressions to be separated by newlines, which can improve the readability of your program.

JavaScript 允许三元操作数之间有换行，可以提高程序的可读性。

For example:

例如：

var foo = bar > baz ? value1 : value2;

The above can be rewritten as the following to improve readability and more clearly delineate the operands:

上面的代码可以重写为以下形式，来提高可读性，更加清晰的描述三元操作数。

var foo = bar > baz ?
    value1 :
    value2;

Rule Details

This rule enforces or disallows newlines between operands of a ternary expression. Note: The location of the operators is not enforced by this rule. Please see the operator-linebreak rule if you are interested in enforcing the location of the operators themselves.

该规则强制或禁止在三元操作数之间有换行。注意：操作符的位置不是该规则强制的。如果你对操作符的位置感兴趣，可以查看operator-linebreak。

Options

This rule has a string option:

该规则有一个字符串选项：

• "always" (default) enforces newlines between the operands of a ternary expression.
• "always" (默认) 强制三元操作数之间有换行。
• "always-multiline" enforces newlines between the operands of a ternary expression if the expression spans multiple lines.
• "always-multiline" 如果表达式跨越多个行，则在三元表达式的操作数之间强制换行。
• "never" disallows newlines between the operands of a ternary expression (enforcing that the entire ternary expression is on one line).
• "never" 禁止三元操作数之间有换行 (强制整个三元表达式在同一行).

always

This is the default option.

这是默认选项：

Examples of incorrect code for this rule with the "always" option:

默认选项 "always" 的 错误 代码示例：

/*eslint multiline-ternary: ["error", "always"]*/

foo > bar ? value1 : value2;

foo > bar ? value :
    value2;

foo > bar ?
    value : value2;

Examples of correct code for this rule with the "always" option:

默认选项 "always" 的 正确 代码示例：

/*eslint multiline-ternary: ["error", "always"]*/

foo > bar ?
    value1 :
    value2;

foo > bar ?
    (baz > qux ?
        value1 :
        value2) :
    value3;

always-multiline

Examples of incorrect code for this rule with the "always-multiline" option:

/*eslint multiline-ternary: ["error", "always-multiline"]*/

foo > bar ? value1 :
    value2;

foo > bar ?
    value1 : value2;

foo > bar &&
    bar > baz ? value1 : value2;

Examples of correct code for this rule with the "always-multiline" option:

/*eslint multiline-ternary: ["error", "always-multiline"]*/

foo > bar ? value1 : value2;

foo > bar ?
    value1 :
    value2;

foo > bar ?
    (baz > qux ? value1 : value2) :
    value3;

foo > bar ?
    (baz > qux ?
        value1 :
        value2) :
    value3;

foo > bar &&
    bar > baz ?
        value1 :
        value2;

never

Examples of incorrect code for this rule with the "never" option:

选项 "never" 的 错误 代码示例：

/*eslint multiline-ternary: ["error", "never"]*/

foo > bar ? value :
    value2;

foo > bar ?
    value : value2;

foo >
    bar ?
    value1 :
    value2;

Examples of correct code for this rule with the "never" option:

选项 "never" 的 正确 代码示例：

/*eslint multiline-ternary: ["error", "never"]*/

foo > bar ? value1 : value2;

foo > bar ? (baz > qux ? value1 : value2) : value3;

When Not To Use It

You can safely disable this rule if you do not have any strict conventions about whether the operands of a ternary expression should be separated by newlines.

如果你对三元操作数是否有换行没有严格约定，你可以禁用此规则。

Related Rules

• operator-linebreak

Compatibility

• JSCS: requireMultiLineTernary

Version

This rule was introduced in ESLint 3.1.0.

该规则在 ESLint 3.1.0 中被引入。

Resources

• Rule source
• Documentation source